Question

我正在尝试将消息中的表中的特定列打印给用户。这是表格示例

StateCode  |   EffectiveDate   |   ExpirationDate
---------------------------------------------
  AK       |   2011-12-31      |   2012-12-31
  AL       |   2011-12-31      |   2015-12-31

所有州的

等等。我想要做的是选择GETDATE（）不在EffectiveDate和ExpirationDate之间并向用户输出消息。 Select语句我有效但如果返回多个状态则会崩溃。有什么方法可以保存列表然后打印出来吗？或者我可以采取的另一种方法

继承我现在使用的Select Query，它适用于1状态返回

DECLARE @missingStates varChar(30)
SET @missingStates = Select StateCode FROM StateTable
   WHERE GETDATE() NOT Between StateTable.EffectiveDate AND StateTable.ExpirationDate

PRINT 'States Missing Effective Models'
PRINT @missingStates

感谢您的帮助

Answer 1

您必须将多个值组合成一个变量：

DECLARE @missingStates varChar(30)
SET @missingStates = ''

 Select @missingStates = @missingStates + Code + ' ' FROM StateTable
   WHERE GETDATE() NOT Between StateTable.EffectiveDate AND StateTable.ExpirationDate

PRINT 'States Missing Effective Models'
PRINT @missingStates

Answer 2

要获得逗号分隔的状态列表，请执行以下操作：

Select case when @missingStates = ''
            then @missingStates = Code 
            else @missingStates = @missingStates + ',' + Code 
       end as states
FROM StateTable
WHERE GETDATE() NOT Between StateTable.EffectiveDate AND StateTable.ExpirationDate

SQL，从选择查询中打印一列

2 个答案: